Warhead breakup sensor

ABSTRACT

A SENSING MEANS LOCATED WITHIN THE EXPLOSIVE WARHEAD OF A MISSILE TO DETECT ONLY ACTUAL BREAKUP DAMAGE OF THE WARHEAD AND BEING UNAFFECTED BY OTHER MISSILE BODY DAMAGE.

E. J. DAVIS ETAL 3,717,6

WARHEAD BREAKUP SENS OR Filed May 20. 1966 mwl 80 S W I U V D C A O D LRM J C J w D. R WW LVA WU DA O EPMD RICHARD L. HIGUERA INVENTORS UnitedStates Patent WARE-HEAD BREAKUP SENSOR Edward J. Davis, Riverside, andPaul E. Cordle and Melvin .ll. McCubbin, China Lake, Califi, Donald W.Lockwood, Corvallis, reg., and Richard L. Higuera, Riverside, Calif.,assignors to the United States of America as represented by theSecretary of the Navy Filed May 20, 1966, Ser. No. 552,677

Int. Cl. F42c 11/00 US. Cl. 102-701 R 5 Claims ABSTRACT OF THEDKSCLOSURE A sensing means located within the explosive warhead of amissile to detect only actual breakup damage of the warhead and beingunaffected by other missile body damage.

The invention herein described may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

The present invention relates to missile fuzing devices and moreparticularly to a missile having warhead breakup sensing means forinstantaneously detonating the missile warhead in the event the warheadbegins to breakup upon impact with a target.

A primary objective in fuze design is to detonate a warhead at theoptimum time during target encounter to produce maximum warheadeffectiveness. There are two types of fuze triggering devices that havebeen used to sense contact with a target; these are the inertia anddeformation type switches. Deformation type switches have been used inthe past, mounted in the nose or other exterior surfaces, where theywere readily subject to surface contact. Also, delay type detonationswitches are used in fuze systems for firing a warhead after a brieftime interval. Missiles often have fuzing systems which incorporate morethan one type firing mode, such as instantaneous and one or more delaymodes. A delay mode can permit a degree of penetration of a target by amissile before detonation depending upon the integrity of the missileand target and the delay time. Often upon impact with a target a contacttype triggering device will detonate a missile warhead before it haspenetrated sufiiciently to give maximum effectiveness; and in otherinstances, where a delay type detonator is used to allow time forpenetration of a tar-get, the warhead is frequently disintegrated by theimpact prior to the fuze detonation resulting in a very significantreduction in the effectiveness of the warhead. The unknown factor ofpenetration capability of a warhead has always been a problem in thedevelopment of more effective weapons. Extensive and costly tests arerequired to determine the penetration capability of a warhead, but evenwhen this information has been determined target resistance is notalways known or available. The improper selection of fuze firing modeoften results, as pointed out, in a low order detonation due todeflagration or deformation of a warhead not capable of remainingintegral during target impact. Such failure situations can be eliminatedby using the warhead breakup sensing technique of the instant inventionto detonate a warhead.

The present invention is a new concept in target encounter which sensesinternal derangement of a missile warhead. Its purpose is not as acontact trigger for sensing surface contact of missile or warhead withtarget, as has been done in the past, but senses when actual damage tothe warhead commences. In other words, the instant device senses warheaddisintegration during target impact or penetration and triggersdetonation before the effectiveness of the warhead is excessivelyreduced due to warhead disintegration. This invention involves a breakupsensor or trigger strategically located inside the warhead usually nearthe forward portion thereof, and protected from damaging surface contactbut not protected from forces which cause disintegration of the warheadexplosive. The breakup sensor is used in the fuze circuitry to over-rideother fuze firing modes in order to detonate the warhead for optimumeffectiveness. The breakup sensor is essentially a switch, such as acrush trigger, which is closed when crushed within the warhead thusinitiating the instantaneous detonator.

It is an object of the invention to provide a missile having a warheadbreakup sensor.

Another object of the invention is to provide a missile warhead havingan over-ride system for causing instantaneous detonation uponcommencement of warhead breakup.

Still another object is to provide a fuze system for preventing loss ofwarhead effectiveness as a result of de flagration or deformation bycausing detonation thereof before excessive damage occurs.

A further object of the invention is to provide means within a warheadfor sensing breakup thereof.

Other objects and many of the attendant advantages of this inventionwill become readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawings wherein:

FIG. 1 is a diagrammatic illustration of an embodiment of the inventionshowing a weapon having a warhead, with a breakup sensor buried withinthe warhead itself and connected to the fuze system.

FIG. 2 shows another embodiment with the breakup sensor located in arecess in the warhead wall.

The weapon shown in FIG. 1 of the drawing, by way of example, involves amissile body 10 including a warhead which usually consists of an outerjacket 12, of steel or the like, containing explosive 14. A fuze system16 which may involve one or more firing modes is provided for firing adetonator 18 to initiate the warhead.

In addition to the regular fuze system a warhead breakup sensor 20 isprovided. The warhead breakup sensor may consist of a deformation typeor crushable trigger switch or similar means for sensing breakup ordisintegration of the warhead due to defiagration or deformation. Thebreakup sensor 20 is buried within the warhead itself and may be locatedat any desirable position therein. The most likely position for a sensorwould be in a forward portion of the warhead since distintegration of awarhead due to impact with a target of excessive resistance would mostlikely commence in that area. Also, more than one breakup sensor can beused, if desired, and located in several different parts of a warhead.Breakup sensor 20 is connected by means of electrical leads 22 to fuzesystem 16. Whenever sensor 20 detects warhead deflagration ordeformation or both it acts to over-ride any delay mode of the fuzesystem to instantaneously fire the warhead assuring a detonation of highorder. Without a breakup sensor, damage to the warhead from attemptedtarget penetration could easily result in a failure. Where desirable awarhead breakup sensor could be used as the primary, if not the sole,fuze triggering means.

If desired, especially where a shaped charge warhead is used, thebreakup sensor 20 can be positioned or buried in a recessed portion orcavity 24 along a wall of the warhead where it will be protected fromdamaging surface contact but not protected from warhead distintegrationforces, as shown in FIG. 2.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood that within 3 the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed is:

1. In a weapon comprising a missile body, and an explosive warhead andfuze firing system in said missile body, the improvement comprising:

(a) a Warhead breakup sensing means,

(b) said breakup sensing means being positioned in said warhead Wheredamage to the warhead is to be sensed to prevent slow order detonationand where said sensing means is protected from damaging surface contactto the missile body when said weapon encounters a target but notprotected from warhead distintegration forces due to deflagration anddeformation of the explosive warhead portion of said weapon upon targetimpact,

(c) said breakup sensing means being connected to said fuze system forcausing instantaneous firing of said warhead upon sensing commencementof said warhead disintegration before excessive loss of warheadefiectiveness occurs,

(d) said breakup sensing means sensing only actual warhead damage anddisintegration and not being affected by mere surface contact forces orother 4 missile body deformations which do not cause actual damage andbreakup of the explosive Warhead. 2. A device as in claim 1 wherein saidwarhead breakup sensing means is a crushable trigger type switch.

3. A device as in claim 1 wherein said warhead breakup sensing means isburied within the warhead explosive.

4. A device as in claim 1 wherein said warhead breakup sensing means islocated in a recess in the warhead wall.

5. A device as in claim 1 wherein said warhead breakup sensing means isused to over-ride any other firing mode in said fuze system.

References Cited UNITED STATES PATENTS 1,374,705 4/1921 Wright 10270.2 X2,485,887 10/1949 Jordan 1O270.2 X 2,728,296 12/1955 Meister 10256 XSAMUEL W. ENGLE, Primary Examiner US. Cl. X.R. 1022, 75

